I just bought a fan for my Little Giant. I didn't have any directions, so I opened up the thermostat box and connected wires. It's a very simple setup, but you do need a very basic concept of wiring to do it. I did make my husband plug it in to test. LOL. Well, the fan would only kick on when the light of the thermostat was on. I thought that was odd, so I rewired it. The problem was that I had one of the fan wires connected to the thermostat wire. Once I connected both black wires of the fan to both black wires of the incubator wall plug it worked. The fan is now constantly on, and I'm pretty sure that's how it's supposed to be.